/*
  ==============================================================================

   This file is part of the JUCE 6 technical preview.
   Copyright (c) 2017 - ROLI Ltd.

   You may use this code under the terms of the GPL v3
   (see www.gnu.org/licenses).

   For this technical preview, this file is not subject to commercial licensing.

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

namespace juce
{

//==============================================================================
/**
    A three-coordinate vector.

    @tags{OpenGL}
*/
template <typename Type>
class Vector3D
{
public:
    Vector3D() noexcept                                        : x(), y(), z() {}
    Vector3D (Type xValue, Type yValue, Type zValue) noexcept  : x (xValue), y (yValue), z (zValue) {}
    Vector3D (const Vector3D& other) noexcept                  : x (other.x), y (other.y), z (other.z) {}
    Vector3D& operator= (Vector3D other) noexcept              { x = other.x;  y = other.y;  z = other.z; return *this; }

    /** Returns a vector that lies along the X axis. */
    static Vector3D xAxis() noexcept                        { return { (Type) 1, 0, 0 }; }
    /** Returns a vector that lies along the Y axis. */
    static Vector3D yAxis() noexcept                        { return { 0, (Type) 1, 0 }; }
    /** Returns a vector that lies along the Z axis. */
    static Vector3D zAxis() noexcept                        { return { 0, 0, (Type) 1 }; }

    Vector3D& operator+= (Vector3D other) noexcept          { x += other.x;  y += other.y;  z += other.z;  return *this; }
    Vector3D& operator-= (Vector3D other) noexcept          { x -= other.x;  y -= other.y;  z -= other.z;  return *this; }
    Vector3D& operator*= (Type scaleFactor) noexcept        { x *= scaleFactor;  y *= scaleFactor;  z *= scaleFactor;  return *this; }
    Vector3D& operator/= (Type scaleFactor) noexcept        { x /= scaleFactor;  y /= scaleFactor;  z /= scaleFactor;  return *this; }

    Vector3D operator+ (Vector3D other) const noexcept      { return { x + other.x, y + other.y, z + other.z }; }
    Vector3D operator- (Vector3D other) const noexcept      { return { x - other.x, y - other.y, z - other.z }; }
    Vector3D operator* (Type scaleFactor) const noexcept    { return { x * scaleFactor, y * scaleFactor, z * scaleFactor }; }
    Vector3D operator/ (Type scaleFactor) const noexcept    { return { x / scaleFactor, y / scaleFactor, z / scaleFactor }; }
    Vector3D operator-() const noexcept                     { return { -x, -y, -z }; }

    /** Returns the dot-product of these two vectors. */
    Type operator* (Vector3D other) const noexcept          { return x * other.x + y * other.y + z * other.z; }

    /** Returns the cross-product of these two vectors. */
    Vector3D operator^ (Vector3D other) const noexcept      { return { y * other.z - z * other.y, z * other.x - x * other.z, x * other.y - y * other.x }; }

    Type length() const noexcept                            { return std::sqrt (lengthSquared()); }
    Type lengthSquared() const noexcept                     { return x * x + y * y + z * z; }

    Vector3D normalised() const noexcept                    { return *this / length(); }

    /** Returns true if the vector is practically equal to the origin. */
    bool lengthIsBelowEpsilon() const noexcept
    {
        auto epsilon = std::numeric_limits<Type>::epsilon();
        return ! (x < -epsilon || x > epsilon || y < -epsilon || y > epsilon || z < -epsilon || z > epsilon);
    }

    Type x, y, z;
};

} // namespace juce